Infertility affects an estimated ten million Americans annually. A critical "gateway" diagnostic test used in over 10,000 USA labs is sperm morphology, one of the most predictive measures of fertility potential that often determines the course of clinical intervention. Morphology also is an important measure of toxic exposure from environmental and occupational sources. Unfortunately, morphology analysis often is the most unreliable and difficult part of a semen profile to interpret, due primarily to lack of a useful Standard. Several schemes exist, none of which have adequate agreement among laboratories. The goal of the proposal is to determine the feasibility of developing a consensus Standard for sperm morphology associated with reproducible visual and morphometric characteristics. A set of sperm images illustrating different typologies will be created with emphasis on the most problematic -- normal and borderline normal forms. Approximately 100 expert andrologists will classify each sperm image and describe the visual characteristics associated with classification. Data will be analyzed to determine the images with the most agreement and disagreement using Cohen's Kappa measure. Correlation of classification will be made with specific visual parameters such as oval shape, smoothness, perceived length to width ratio. The end results of the feasibility study will be: 1) a set of images with good agreement and a set needing more study and clarification (low Kappa); 2) data on agreement that can be used to set sample sizes needed for images and reviewers in the Phase II application; 3) a better understanding of what images are problematic and why; 4) a Phase II application to create a definitive Standard in multimedia formats. The image sets and data would be expanded and developed in a subsequent Phase II application to create a Standard multimedia sperm atlas for training and reference. In Phase II, a Computer Assisted Semen Analyzer (CASA) would be used to rapidly find multiple images for each sperm type. A comprehensive image set based on community consensus will be developed into multimedia teaching and quality control tools. The Standard would be available in print and CD and as an lnternet on-line subscription service for internationally accessible laboratory training and reference.